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Laminating Western Red Cedar Cove And Bead Strips to Make Yard

I have a number of leftover western red cedar cove and bead strips from a previous canoe build. There are enough of them that they could be laminated into a blank for the yard for my Caledonia Yawl. The yard, based on the plans, is 2-1/8"X 13 feet long and my strips are 17 (+) feet so no scarfing would be required. It would make do a nice light yardarm but would it be strong enough? There are no fittings that will be screwed to the yard. If it is a reasonable thing to do should I use epoxy for the glue-up or titebond III?

Re: Laminating Western Red Cedar Cove And Bead Strips to Make Yard

Using up leftover materials is good. Light is good, for a yard. Either adhesive would be fine. But would it be strong enough and have suitable characteristics. I'd say no, and no. 'Strength' in common useage is often a shorthand for MoE... modulus of elasticity. WRC is not 'strong' in that way. But there are other measures of strength, and WRC doesn't measure up well in any of the relevant areas.

If you do decide to go ahead, I'd recommend one thing. Compare the 'strength' numbers for WRC vs. whatever species was specified (probably Sitka Spruce or Douglas Fir), and beef us the yard scantlings accordingly. That'll at least take one issue off the table.

Re: Laminating Western Red Cedar Cove And Bead Strips to Make Yard

Originally Posted by David G

Using up leftover materials is good. Light is good, for a yard. Either adhesive would be fine. But would it be strong enough and have suitable characteristics. I'd say no, and no. 'Strength' in common useage is often a shorthand for MoE... modulus of elasticity. WRC is not 'strong' in that way. But there are other measures of strength, and WRC doesn't measure up well in any of the relevant areas.

If you do decide to go ahead, I'd recommend one thing. Compare the 'strength' numbers for WRC vs. whatever species was specified (probably Sitka Spruce or Douglas Fir), and beef us the yard scantlings accordingly. That'll at least take one issue off the table.

Thanks for your reply, I will review the specs on Sitka Spruce or Douglas Fir vs WRC.

Re: Laminating Western Red Cedar Cove And Bead Strips to Make Yard

Originally Posted by Steamboat

Thanks for your reply, I will review the specs on Sitka Spruce or Douglas Fir vs WRC.

Just know that - even if you beef it up a bit - you'll still be pushing the envelope. Have seen a few spars fail under load, and under way... I'm not personally inclined to do that. Not even with my personal projects, where I'm willing to be more experimental. YMMV, of course.

Re: Laminating Western Red Cedar Cove And Bead Strips to Make Yard

Plus the fact that WRC tends to be "brittle", which sorta gets into David's modulus comment, but we're talking about a difference like that between cast iron and steels. Cast iron would have a brittle fracture, while the steel is a bit more "elastic". With a yard being bent, I'd want that elasticity and forgiveness.

"The pessimist complains about the wind; the optimist expects it to change; the realist adjusts the sails."
-William A. Ward

Re: Laminating Western Red Cedar Cove And Bead Strips to Make Yard

Right about the glass. WRC canoes and kayaks put all of their loads on the glass skins. The WRC is little more than filler. If you made the spar up of your leftover strips and then laminated a glass sleeve over it, you'd have a pretty strong yard.
Something like this:http://www.fibreglast.com/product/Br...raided_Sleeves

Re: Laminating Western Red Cedar Cove And Bead Strips to Make Yard

Originally Posted by Woxbox

Right about the glass. WRC canoes and kayaks put all of their loads on the glass skins. The WRC is little more than filler. If you made the spar up of your leftover strips and then laminated a glass sleeve over it, you'd have a pretty strong yard.
Something like this:http://www.fibreglast.com/product/Br...raided_Sleeves

Aye... but then you will very likely have created a yard that is far stiffer than the designer planned on. To some extent - the sailmaker (if he's both engaged and knowledgeable) can obviate that effect some. But enough? I don't know.

We're getting further and further into uncharted waters - which are typically full of 'unintended consequences'.

I'd say - give up the lovely fantasy of using up your cedar, and just Build To Plan. Always the best idea anyway.

It's all very well to speculate, invent, McGuyver, and cobble together a creative approach... but - in the end - someone is going to have to SAIL this boat.

Re: Laminating Western Red Cedar Cove And Bead Strips to Make Yard

Most sailmakers would delight in a yard which is "too stiff". One of the biggest hassles we face in designing and cutting sails is making allowances for spar bend. If you cut the sail to account for all the potential bend in windy conditions, that excess tends to create too much unwanted draft in light air. In 37 years of making sails, nobody ever brought me a spar which was too stiff unless it was dimensionally way too thick. In that case, it was much more a weight aloft problem than one of stiffness.

Re: Laminating Western Red Cedar Cove And Bead Strips to Make Yard

Originally Posted by Woxbox

Right about the glass. WRC canoes and kayaks put all of their loads on the glass skins. The WRC is little more than filler. If you made the spar up of your leftover strips and then laminated a glass sleeve over it, you'd have a pretty strong yard.
Something like this:http://www.fibreglast.com/product/Br...raided_Sleeves

Your suggestion kept tickling my brain so I did a rough calculation: DF spar would be 10.2lb base on average density and the WRC spar with your 10oz glass sleeve plus epoxy would be about 7.4lb. A 30% reduction in weight aloft is not a trivial difference. It is not a cheep experiment but how would you test the glassed WRC/glass spar before putting it into service? OK, to some this is a risky idea but what if we learn something new from it?

I'm not about to put this spar into service and take my wife sailing with an experimental entity unless there is a rational way to test it without destroying it.

Re: Laminating Western Red Cedar Cove And Bead Strips to Make Yard

I was thinking you could glue two strips together to make one stave for a birdsmouth spar. But 1/2” by 3/4” staves gives you a spar of just under 2” diameter. If the solid fir spar should be 2 1/8” and a hollow spar should be bumped up 10% I’d also want to bump it a bit extra for the less strong wood. Maybe 2 3/8” or so. That means your extra strips won’t really help you out here.

Re: Laminating Western Red Cedar Cove And Bead Strips to Make Yard

It sure looks to me that those scantlings are figured for stiffness, not for ultimate strength. I can't imagine breaking that yard, short of sailing under a low bridge. The only detail you might want to consider for peace of mind is to fit a solid plug where the halyard will be made off.